Electrical locking pin terminal

ABSTRACT

A hollow tubular locking pin terminal for securement in a sphinctered opening is provided with a resilient lance means extending axially within the terminal and having a locking member extending through an opening in the wall of the terminal to lock behind the constriction in the sphinctered opening. The tubular pin terminal including the resilient lance and locking member are all made from a unitary blank.

United States Patent [72] Inventor Frederick Jean Maltais Camp Hill, Pa.[21] Appl. No. 6,104 [22] Filed Jan. 27, 1970 [45] Patented Oct. 12,1971 [73] Assignee AMP Incorporated Harrisburg, Pa.

[54] ELECTRICAL LOCKING PIN TERMINAL 7 Claims, 5 Drawing Figs.

[52] US. Cl 339/217 S [51] Int. Cl H0lr 9/12 [50] Field of Search339/217, 91, 252,213, 256, 258

[56] References Cited UNITED STATES PATENTS 3,085,222 4/1963 Watts339/217 3,425,029 1/1969 Zak 339/252 3,513,438 5/1970 Henschen et a1.339/217 F OREIGN PATENTS 1,355,758 2/1964 France 339/217 S PrimaryExaminer-Marvin A. Champion Assistant Examiner-Robert A. I-IaferAttorneys-Curtis, Morris and Satford, William J. Keating,

Ronald D. Grefe, William Hintze, Adrian .1. La Rue, Frederick W. Raring,Jay L. Seitchik and John P. Vandenburg ABSTRACT: A hollow tubularlocking pin terminal for securement in a sphinctered opening is providedwith a resilient lance means extending axially within the terminal andhaving a locking member extending through an opening in the wall of theterminal to lock behind the constriction in the sphinctered opening. Thetubular pin terminal including the resilient lance and locking memberare all made from a unitary blank.

PATENTEU U 1219?! 3,613,052

I/Vl/E/VTOR FREDERICK JEAN MALTAIS ELECTRICAL LOCKING PIN TERMINAL Theinvention relates to an electrical locking pin terminal and the methodof making such terminal.

It is essential in many cases, to ensure that a pin terminal afterinsertion into a mating socket or opening, be securely held therein sothat it does not fall out due to rough handling or vibration and that itmay not be easily withdrawn by persons unauthorized to do so. To thoseends, the mating opening or socket for the terminal is sphinctered orconstricted intermediate its ends. The terminal is made hollow andprovided with a locking member or lance which is mounted on a resilientmember within the terminal and extends through an opening therein tolook behind the constriction when housed in the opening to prevent itswithdrawal. The locking member is so mounted and constructed that uponan attempt to withdraw the pin from the socket, the lance tends toproject still further from the slot and the forward face of the lance orlocking member is forced against the edge of the opening in the pinbody, preventing lance depression and locking the pin in place.

In order to mass produce such pin terminal in a simple and economicalmanner, I provide a single blank which may be stamped out in a singleoperation and from which the hollow pin terminal, including the lockingmember with its resilient mounting, may be integrally formed.

It is therefore an object of this invention to provide a locking pinterminal especially for use with a sphinctered opening.

It is a further object of the invention to provide a complete lockingpin terminal out of a single metal blank.

It is still a further object of the invention to provide a pin terminalwhich cannot fall out of a mating hole or be extracted from such holewithout the use of a tool.

These and other objects and advantages of the invention will appear morefully in the description of the invention with specific reference to thedrawings, in which:

FIG. 1 shows the locking pin terminal of the invention in perspective;

FIG. 2 is a cross section of the pin terminal of FIG. 1 along the line2-2, with the right-hand end portion showing the conductive connectionto the terminal omitted;

FKG. 3 is a plan view of the blank from which the pin terminal of FIG. 1is formed, an end portion thereof being omitted;

FlGS. 4 and 5 are cross-sectional views of the terminal taken alonglines 4-4 and 5-5 respectively of FIG. 2.

First referring to the blank from which the pin terminal is formed, itcan be seen that the blank, which is of flat stock material, has a bodyportion 4 which is substantially rectangular in shape having straightparallel sides 3 and 3' and is substantially crenellated at the forwardend 5, as shown in FIG. 3. At the other end of the body portion 4, theblank is necked down, as at 9, and terminates in a further region, notshown in FIG. 3, but shown to the right in FIG. 1. Such region,designated as 1 1, is part of the flat stock material of the blank whichis bent into tubular forms as later described and thus crimped in aconventional manner to a conductor to form an electrical connectiontherewith. A rectangular slot or opening 2 is provided in the bodyportion 4 of the blank at a substantially central location thereof. Anarm or tongue member 6, spaced from one side of the body portion andextending therealong for a short distance is integrally connected to theside of the body portion 4 of the blank by a bridging section 8. Forpurposes to be described later, the body portion 4 is notched, as at 10,adjacent to the side of the bridging section closer to the opening 2.The distance between the outer edge 7 of the tongue and the bottom ofthe notch 10 is substantially that between side 3 and the longitudinalcenter of the slot 2.

The free end of the arm or tongue 6 terminates at substantially the samedistance from one end of the blank as the farthest edge of the openingor slot 2 is from that end. The terminal portion 12 at the free end ofthe arm extends laterally outward and is of substantially the samelength as the slot. The laterally outermost edge 14 of the portion 12extends at an angle to the straight side 3 of the body portion 4, beingfurther from the side 3 at the extreme free end of the tongue 6. Therear edge 16 of the outstanding portion 12 tapers forwardly as itapproaches the same side. Between the slot 2 and the necked-downnarrower portion 9, the blank is provided with pairs of parallelcoextensive slits 20 extending in a transverse direction. The forwardand rearward slits 20 are in respective alignment in a directiontransverse to the body portion 4. Rearwardly of the slits 20, the blankis further provided with pairs of parallel coextensive slits 22extending lengthwise of the body portion. Adjacent the forward end ofthe body portion 4 of the blank, the side 3' is provided with a notch 24at a location transversely opposite to that of the bridging section 8and is of a length somewhat exceeding that of the last mentionedsection. As can be seen from the above description of the blank fromwhich the locking terminal pin is made, it can be stamped out of flatstock or otherwise formed of normally used electrical terminalmaterials.

To form the locking pin terminal shown in FIG. 1, the bridging sectionin FIG. 3 may first be bent upwardly through an arc of from the plane ofthe paper. The blank is then bent into tubular form about a centrallongitudinal axis so that the tongue 6 is encompassed to extendsubstantially along the axis when the sides 3, 3' of the body portionmeet. At this point, the outstanding section 12 will extend into theopening 2. Before the bending operation, the crenellations at theforward end of the blank can be dished and so shaped that when the blankassumes the tubular form, they can be folded over to meet at their sideand forward edges as shown in FIG. 1, to form a smooth and roundedforward end for easy insertion into an opening. Also, the materialbetween the slots 20 and 22 may be forced outwardly to form projections24 and 26 respectively without breaking or tearing the material beforebending the blank into tubular form. Preferably however, the blank maybe formed into the desired shape on a mandrel which is slitted axiallyalong a portion of its length, to accommodate the tongue or arm 6 and topermit the enlarged portion 12 to extend into the opening and to thenslide the formed pin off the mandrel. It is obvious, of course, that theend of the mandrel corresponding to the forward or nose end of theterminal would be round and smooth so as to allow the crenellated end ofthe blank to be formed thereon to assume the same shape, as shown inFIGS. 1 and 2. The resultant pin terminal is therefore tubular in shapeand encompasses therewithin a lance means provided by the arm 6 andenlarged locking portion 12 integrally formed from the metal of the pin.The length of the lance means and the use of the bridging section 8 forhinging it to the pin proper, is closed to provide a low lancedepression force and the stress at the hinge area is within theallowable working stress of normally used electrical materials. Thenatural resiliency of the metal tends to project the locking portion 12of the lance means through the opening 2 regardless of the number oftimes the locking portion is depressed. The opening 26 in a block B,into which the pin terminal of the invention is inserted and secured, issphinctered. Such an opening may be formed by counterboring the rear endof the opening or both ends if so desired, in the manner shown in FIG.2. As can be seen, the projecting members or stops 24 are spacedrearwardly of the rearmost edge of the locking member 12 by at least thethickness of the wall 30 which constricts the diameter of the opening28. When the pin terminal is inserted into the opening 28 in the block Bwith the forward end or nose 5 first in the direction of the arrow, thelance means is depressed as the locking member 12 engages the inner edgeof wall 30 until it passes the forward surface of the wall andresiliently locks thereagainst. At this time the projections or stopsengage the rear surface of the wall so that the pin terminal isprevented from either forward or rearward movement. The stops 26 on thepin terminal are of a height to substantially make contact with the wallof the counterbored opening 28 to prevent movement of the pin radiallyof the opening.

As fully shown and described above, the pin terminal is so constructedthat when locked in a sphinctered opening any attempt to extract it fromsuch opening, by pulling in a direction counter to the arrow, wouldcause the rear edge 16 of the locking member to cam against the edge ofwall 30 and pull the lance means upwardly and locking member further outof the pin body. Should the lance means tend to bend or buckle undergreater extraction force, the forward edge 18 of the locking portionwould be forced against the forward edge of slot 2 in the pin body, andby reason of its forwardly facing angle, prevent lance depression andlock the pin place. Where the opening in the block is counterbored atits forward as shown in FIG. 2, the pin may be extracted by sliding aflat rigid member over the locking member in the wider portion of theopening to depress it. Where the block B, with one or more openingstherein, is mounted at a location where its forward side is notaccessible to authorized personnel, it is obvious that the locking pincould not be withdrawn. If the block B is utilized with electricaldevices subjected to jarring or vibration, the lockin pin of theinvention is held therein so securely that danger of falling out andperhaps disconnecting a circuit, is avoided.

While a preferred embodiment of the invention has been illustrated, manyobvious modifications may be made without departing from the spirit andscope of the invention and the claims are to be construed as coveringsuch obvious modifications.

What is claimed is:

1. A tubular electrical terminal member for insertion into an opening ina body which is constricted by an inwardly directed wall having forwardand rear surfaces comprising, an opening in the wall of the tubularmember, resilient lance means connected to the tubular member andextending in an axial direction interiorly thereof, the lance meansbeing provided adjacent its free end with locking means having forwardand rearward edges extending therefrom and projecting through theopening, the lance means being of a greater width than thickness andintegrally connected at its forward end by tongue means to the tubularmember adjacent its forward end and with a side defining its widthextending in a plane substantially parallel to a radial plane, thetubular member having means at its rear end for connection to aconductor.

2. A tubular electrical terminal member according to claim 1 in whichthe rear edge of the locking means tapers rearwardly from its connectionto the tongue means, to provide a camming means cooperating with theforward side of the constricting wall upon movement of the tubularmember rearward, to project the locking means further outwardly from theopening.

3. A tubular electrical terminal member according to claim 2 wherein theoutermost edge of the locking means tapers outwardly from its forwardedge to its rear edge to pennit insertion of a tool in the body openingto unlock the lance means from the constricting wall.

4. A tubular electrical terminal member according to claim 3 in whichthe locking means is an integral radial extension of the lance meansadjacent the free end thereof and has its forward edge adjacent to theforward edge of the opening to resist forward movement of the lancemeans.

5. A tubular electrical terminal member according to claim 4 in whichthe forward edge of the locking means tapers rearwardly inward towardthe lance means and cooperates with the forward edge of the opening toprevent inward movement of the lance means.

6. A tubular electrical terminal member according to claim 5 wherein thetubular member is provided with at least one outwardly extendingprojection rearwardly of the locking means at a distance at least equalto the thickness of the constricting wall and of a height to contact therear wall surface, when the tubular member is inserted into the bodyopening.

7. A tubular electrical terminal member according to claim 6 includingat least one further outward projection on said tubular member locatedrearward] of the first projections and of a height to engage the wall ofe opening rearwardly of the constricting wall.

1. A tubular electrical terminal member for insertion into an opening ina body which is constricted by an inwardly directed wall having forwardand rear surfaces comprising, an opening in the wall of the tubularmember, resilient lance means connected to the tubular member andextending in an axial direction interiorly thereof, the lance meansbeing provided adjacent its free end with locking means having forwardand rearward edges extending therefrom and projecting through theopening, the lance means being of a greater width than thickness andintegrally connected at its forward end by tongue means to the tubularmember adjacent its forward end and with a side defining its widthextending in a plane substantially parallel to a radial plane, thetubular member having means at its rear end for connection to aconduCtor.
 2. A tubular electrical terminal member according to claim 1in which the rear edge of the locking means tapers rearwardly from itsconnection to the tongue means, to provide a camming means cooperatingwith the forward side of the constricting wall upon movement of thetubular member rearward, to project the locking means further outwardlyfrom the opening.
 3. A tubular electrical terminal member according toclaim 2 wherein the outermost edge of the locking means tapers outwardlyfrom its forward edge to its rear edge to permit insertion of a tool inthe body opening to unlock the lance means from the constricting wall.4. A tubular electrical terminal member according to claim 3 in whichthe locking means is an integral radial extension of the lance meansadjacent the free end thereof and has its forward edge adjacent to theforward edge of the opening to resist forward movement of the lancemeans.
 5. A tubular electrical terminal member according to claim 4 inwhich the forward edge of the locking means tapers rearwardly inwardtoward the lance means and cooperates with the forward edge of theopening to prevent inward movement of the lance means.
 6. A tubularelectrical terminal member according to claim 5 wherein the tubularmember is provided with at least one outwardly extending projectionrearwardly of the locking means at a distance at least equal to thethickness of the constricting wall and of a height to contact the rearwall surface, when the tubular member is inserted into the body opening.7. A tubular electrical terminal member according to claim 6 includingat least one further outward projection on said tubular member locatedrearwardly of the first projections and of a height to engage the wallof the opening rearwardly of the constricting wall.